He said: “He’s independent. There’s no pressure on him at all, one way or the other. I just want him to find the truth and to tell us.

“What if he comes back and tells me things I didn’t anticipate? I have no reason to say he is going to find anything that will shock us.

“If he does, we’ll have to act accordingly.”

Dr Billings said he has made his views ‘perfectly clear’ to senior police over instances where officers have failed on CSE. He said: “The HMIC – Her Majesty’s Inspectorate of Constabulary – report earlier this year quotes an officer talking about ‘naughty children.’

“That clearly indicates he doesn’t understand grooming. I have to be sure that whoever that was is either retrained or moved.

“I make clear to the senior command team that anybody who shows attitudes of that kind has to be moved, because they are clearly incapable of understanding what they are being asked to do.”

He said ‘cultural change’ needs to happen across the force to tackle abuse.

He said: “There have been generational issues and the older generation have now moved on. The younger generation want to get it right, and understand that they have to.

“This is not the most popular area of the police force in which to serve, so increasingly I think we can be confident that the people who come there are the ones who want to make it right.

“That’s not to say you’re not going to find the odd person who is unreconstructed. In all walks of life, that’s true.

“Cultural change in any organisation is the most difficult thing you can effect.”

Dr Billings says that in future, police will have to be ‘savvy’ to grooming, which is increasingly moving online.

He added: “If you think about grooming, it would be fatally easy now to focus so much on on-street grooming that we lose sight of the fact that grooming is moving onto the internet, and the new scandals may well be things that are happening online.